Modern cars have sophisticated systems to responsible for not only the performance of the vehicle but the amount of unwanted emissions that released into the atmosphere. These systems include the Evaporative Emission System which involves fuel fumes, Exhaust Emission system, including the secondary air system and the catalytic converter with its oxygen sensors and Exhaust gas recirculation system, minimizes the amount of pollution your vehicle produces from the act of running. Malfunctions in any of these Emission Systems will result in your “check engine” (MIL) coming on. This will preclude acquiring an Inspection sticker.